The Applicant has invented an ink jet printhead that is capable of generating text and images at a resolution of up to 1600 dpi.
In order to achieve this, the Applicant has made extensive use of micro electro-mechanical systems technology. In particular, the Applicant has developed integrated circuit fabrication techniques suitable for the manufacture of such printheads. The Applicant has filed a large number of patent applications in this field, many of which have now been allowed.
The printheads developed by the Applicant can include up to 84000 nozzle arrangements. Each nozzle arrangement has at least one moving component which serves to eject ink from a nozzle chamber. These components usually either act directly on the ink or act on a closure which serves to permit or inhibit the ejection of ink from the nozzle chamber. The moving components are microscopically dimensioned. This is necessary, given the large number of nozzle arrangements per printhead.
Such printheads usually incorporate at least one printhead chip. Where more than one printhead chip is required, the printhead chips are aligned to define what can be regarded as a single, elongate chip. The constraints on the dimensions of silicon wafers which are available result in the necessity for having more than one printhead chip defining a single printhead.
Those of ordinary skill in the field of integrated circuit fabrication techniques will appreciate that the cost of on-chip real estate is extremely high. It is therefore important that a configuration be selected which is efficient and yet which uses a minimum amount of space in order to keep costs to a minimum. Furthermore, it should also be borne in mind that integrated circuit fabrication techniques involve what is generally a deposition and subsequent etching process. As such, devices manufactured in accordance with such techniques are usually layered for ease of construction and also as a result of the methods used to construct such devices. It follows that it is desirable that the structure of the printhead together with the method in which the printhead is manufactured accommodates a layered configuration. This will facilitate ease of construction with a consequent reduction in costs.
The present invention has been conceived by the Applicant in an attempt to provide a printhead chip configuration which effectively overcomes the difficulties identified above.